| 摘要 |
PURPOSE: To ensure a seal for a long period by forming a protective filter device with the combination of a ring shaped screen positioning member and a screen member. CONSTITUTION: This protective filter device 10 comprises an outer holding ring 16 (screen positioning member), a radially inner holding ring 18 and a screen member 20. The ring 16 has a radially outward attaching surface 24 which is aligned and engaged with an inner inward surface forming a part of a main seal device 12. The ring 16 has a radial fitting groove 28 to which the outer edge part of the member 20 is fitted to position the member 20. The radially inner edge part 36 of a main part 32 of the member 20 which is not held is attached to the axial attaching surface 38 of the main part 34 of the ring 18. Thus, the axial and radial movements of the member 20 are prevented and contamination particles are prevented from passing between the member 20 and the ring 16. Thus, the contamination particles are captured, so that they are prevented from being accumulated in a part between the device 12 and the surface 60 of a shaft 58. |
